For detecting the position of and activating block-commutated EC motors, three Hall sensors providing digital signals are typically used. In a one-pole pair sensor magnet set-up, for example, the three Hall sensors provide a clear assignment to six position regions, each of which has 60°. This detection of the absolute electrical position ensures that the positional angle (i.e., the electrical position of the rotor with respect to the position regions) may be clearly identified already when switching on the EC motor such that an EC motor having a number of stator coils can be activated in an optimal manner. If a more precise detection of the positional angle is required or if special types of commutation (150° block length instead of the usual 120° or 180° block length) are to be used, then it may be necessary to double the resolution of the position regions such that twelve position regions are provided for one electrical revolution, each of which have a magnitude of 30°.
Previous position sensor systems having an angular resolution of 30° have, in addition to a first Hall sensor device having the three Hall sensors and the one-pole pair sensor magnet set-up, a second Hall sensor device, which has two second Hall sensors and one second three-pole pair sensor magnet set-up. In this instance, the total number of required Hall sensors is five. This increases the costs and the manufacturing expenditure of the position sensor system.